[TRLog] Multi-Op SS SSB

[KL7RA]

> Does anyone have a schematic of an interface in order to operate 
>Multi-Op Sweepstakes SSB with 2 FT-1000MPs such that when 
>one transmitter is active, the other transmitter is deactivated ? I know 
>footswitches will work, but I'm wanting to do it electronically if 
>possible.
> Before I "reinvent the wheel" I thought I would ask you guys first.
> Thanks and 73,
> Bill  K5GA 

Hello Bill

I was waiting for someone to answer your question that may have
used something to control transmitters for the SS in multi-op. They
may have e-mailed you direct, but if not:

Other then waving at the other op, the only real software feature to 
control separate radios is the Relay Control Port, pin 14, of a selected
parallel port. This pin will toggle high (5 VDC) or low with  ALT R 
keystrokes. Mainly used for SO2R which is one op running two radios
using a relay to control audio or transmitter control.

What you need is a relay that will allow the mic (1) to pass to xmtr one 
when open and mic (2) to pass to xmtr two when closed. This will be
a DPDT relay probably best run by a transistor with the base going
to pin 14. Speaking for Icom, I would keep the mic grounds isolated
from each other and only switch the mic input going to pin one. 

Although this would be a very simple control box it would have two
mic inputs and outputs plus DC and control. Also requires two PCs
with a network and "send qso immediately" enabled. 

I would wave at the second op to get the xmit radio myself. This 
system still works after 50+ years.

This does NOT imply that the ARRL ten meters contest can be 
done the same way. Here it DOES require a control box to get
those hog SSB ops to give up the radio for the poor CW guys
across the room. But that story is best told over beer at Dayton,
late at night, when all the ssb ops are sound asleep.

73 Rich KL7RA